feat(client): add show solution button in TimeLine (#40120)

* feat: add show solution button in TimeLine

* feat: added tests for CertificateSettings and TimeLine

* feat: view button only for projects

* feat: view button visible only for projects

client/src/components/settings/Certification.js

@@ -194,6 +194,7 @@ export class CertificationSettings extends Component {
           block={true}
           bsStyle='primary'
           className='btn-invert'
+          id={`btn-for-${projectId}`}
           onClick={onClickHandler}
         >
           Show Code
@@ -237,6 +238,7 @@ export class CertificationSettings extends Component {
           bsStyle='primary'
           className='btn-invert'
           href={solution}
+          id={`btn-for-${projectId}`}
           rel='noopener noreferrer'
           target='_blank'
         >
@@ -249,6 +251,7 @@ export class CertificationSettings extends Component {
         block={true}
         bsStyle='primary'
         className='btn-invert'
+        id={`btn-for-${projectId}`}
         onClick={onClickHandler}
       >
         Show Code